<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>vue2中实现自定义指令</title>
</head>
<body>
  <div id="app">
    <input type="text" v-focus>
  </div>
  <script src="../node_modules//vue//dist/vue.js"></script>
  <script>
  Vue.directive('focus', {
    inserted: function(el) {
      debugger
      el.focus()
    },
    bind: function () {
      debugger
      console.log('我被绑定了')
    },
    update: function () {
      debugger
      console.log('我被更新了')
    }
  })

  const vm = new Vue({
    el: "#app"
  })
  </script>
</body>
</html>
